CRP and peripheral arterial disease: In the first model, when adjusted for hypertension, GFR, the presence of unilateral or bilateral PAD, and serum CRP tertiles, the odds ratio conferred by serum Cys C in the upper tertile was 6.57 (2.10–20.47), and Cys C remained a significant independent determinant of low ABI (p = 0.016) (Table 5, Model 1).